Whatever it is you are fiddling with under the desk show me NOW. (not a good idea for some of the chaps in 4th year maths).
I was presented with a 'CITHs Theasauras' by my students one year in which they had noted all of my catch phrases - which I didnt know I had. Apparently I like the word miscreant and my top phrase is 'if you are being told to look over there make sure you look over here'. Runner up is 'ask who benefits' and 'if you must watch tv ask yourself if its telling you anything other than buy this, think that, you are quite ugly'